<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>normal</title>
</head>
<body>
    <!-- 块元素自己一行 -->
    <div>aaa</div>
    <div>bbb</div>
    <!-- 行内元素碰到右侧自动折行 -->
    <span>ccc</span>
    <span>ddd</span>
    <span>eee</span>
    <span>fff</span>
    <span>ggg</span>
    <span>ccc</span>
    <span>ddd</span>
    <span>eee</span>
    <span>fff</span>
    <span>ggg</span>
    <span>ccc</span>
    <span>ddd</span>
    <span>eee</span>
    <span>fff</span>
    <span>ggg</span>
</body>
</html>